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A new technological route for fabricating Ge based metal-oxide-semiconductor (MOS) transistors has been developed based on materials research of dielectric layer compositions. Unwanted impurities were encapsulated by using the gate-first process and a modified thermal GeO₂ layer with increased viscosity at the interface with the Ge substrate. Increasing the density of the oxide layer near germanium interaction with the deposited Si₃N₄ film hindered diffusion of impurities into adsorbed by the substrate surface into the transistor channel. This made it possible to increase the electron mobility in the MIS transistor and prevent its decrease at cryogenic temperatures.

Nanowire field-effect transistors are high-sensitivity sensor elements intended for the qualitative and quantitative analyses of biological and chemical substances. Optimization of the sensor operation is one of the key ways of increasing their sensitivity. An algorithm for choosing the operation mode of sensors based on silicon-on-insulator transistors is proposed which provides their maximum response during conductivity monitoring in the detection of target particles.

This paper describes the design and characteristics of the three-spectrum multielement photodetector with a sensitivity range from 0,6 to 12,0 μm, which consists of three lines of photodetectors with the sensitivity ranges from 0,6 to 0,9, from 3 to 5, and from 8 to 12 μm. The methods for manufacturing the lines, the photodetecting device in general, and its photoelectric characteristics are described.

This paper presents a brief review of experimental works in the field of quantum cryptography and quantum key generation by means of single photons in the atmospheric and fiber quantum communication lines. This paper given the description of two experimental devices for quantum key generation, which were designed at the Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences. The results of the study of the dependence of the speed of the quantum key generation on the average number of photons $\mu$ in the laser pulse are given. There is a discrepancy between theory and experiment found for $\mu>0.3$, which may be due to nonzero probability of occurrence of multiphoton pulses in the quantum transmission, which are detected by the single photon detectors as single-photon pulses. When it comes to sieving the quantum key, the cases with simultaneous triggering of several single-photon detectors are ignored because the measurement result is not determined.

This paper presents the review of studies of photoelectric properties of the PbSnTe:In films obtained by molecular beam epitaxy and the photosensitive structures of the far infrared and submillimeter ranges based on these films. The parameters of this type of multielement photodetectors and the detectors based on doped semiconductors and superconductors. Ruled (2 x 128 elements) and matrix (128 x 128 elements) multielement PbSnTe:In based photodetectors with a sensitive edge equal to ~22 m and an operating temperature of T ≤ 16 K are implemented. In the background-free conditions, the power equivalent to the noise reached MES ≤ 10^-18 W/Hz^0.5 for T = 7 K for the radiation source of the absolute black body type at T_ABB = 77 K. The submillimeter region of the spectrum had sensitivity to laser radiation with a wavelength λ ≤ 205 μm and the value of MES ≤ 10^-12 W/Hz^0.5 without optimization of the layout design of the photosensitive member and minimization of the measurement circuit noise. The directions of the development of PbSnTe:In based radiation detectors are considered.

Recent years many flight control systems and industries are employing PID con-trollers to improve the dynamic behavior of the characteristics. In this paper, PID con-troller is developed to improve the stability and performance of general aviation aircraft system. Designing the optimum PID controller parameters for a pitch control aircraft is important in expanding the flight safety envelope. Mathematical model is developed to describe the longitudinal pitch control of an aircraft. The PID controller is designed based on the dynamic modeling of an aircraft system. Different tuning methods namely Zeigler–Nichols method (ZN), Modified Zeigler–Nichols method, Tyreus–Luyben tuning, Astrom–Hagglund tuning methods are employed. The time domain specifications of different tuning methods are compared to obtain the optimum parameters value. The results prove that PID controller tuned by Zeigler–Nichols for aircraft pitch control dynamics is better in stability and performance in all conditions. Future research work of obtaining optimum PID controller parameters using artificial intelligence techniques should be carried out.

We discuss the method of comparing pulse detonation engines (PDE) and engines with combustion in subsonic flow (ramjet) by means of their specific impulse used by the “Center of Pulse-Detonation Combustion” (CPDC). We demonstrate that the method used by CPDC to calculate the performance of PDE overstates the value of specific impulse relative to its actual value by a factor of at least two. In contrast, the values of specific impulse for ramjet are understated. As a result, the specific impulse of PDE significantly exceeds that of ramjet or is close to it. We investigate these misleading conclusions, and demonstrate their complete failure.

The paper reports on shape of a three-dimensional coherent structure in a velocity field of a high-swirl turbulent jet with the bubble-type vortex breakdown. A set of the 3D instantenous velocity fields was measured by using the tomographic particle image velocimetry (tomographic PIV) technique and processed by the proper orthogonal decomposition (POD) method. The detected intensive coherent velocity component corresponded to a helical vortex core of the swirling jet and two secondary spiral vortices. The entire coherent structure was rotating around the jet axis in compliance with the direction of the flow swirl. From the 3D data it is concluded that the dynamics  of the strsucture can be described by a traveling wave equation: Re[A(y, r)×e^{i(mθ + ky − ωt)}] with the number of the spiral mode m = +1 for positively defined k and ω.

The influence of combustion effect on unsteady vortex structure in the form of precessing vortex core was studied using the non-intrusive method of laser Doppler anemometry and special procedure of extracting the non-axisymmetric mode of flow fluctuations. The studies show that combustion has a significant effect on the parameters of such a core, reducing the amplitude (vortex deviation from the burner center) and increasing precession frequency. At the same time, the acoustic sensors detect almost an order reduction in the level of pressure pulsations generated by the precessing vortex core. Moreover, distributions of tangential velocity fluctuations and cross-correlation analysis show that vortex precession is quite pronounced even under the combustion conditions, bringing a significant coherent component to distributions of velocity fluctuations.

On March 12, 2016 a famous Russian scientist in the field of thermophysics, Doctor of Technical Sciences, Professor Ivan I. Gogonin became 80 years of age.